valve-for-mitral-valve-replacement-surgery

I am 68 (Male), Doctors suggesting a mitral valve replacement surgery. Open Heart surgery or Minimal Invasive surgery (MICS)?What valve should I use, Mechanical or Tissue?I am having Atrial Fibriliation, will it continue after surgery? I got to know from a Cardiac Surgeon that tissue valve lasts only 5 years for Atrial Fibriliation patients. Please suggest.